make a folder for your site with a src subfolder containing your site files and a plugins subfolder (empty for now)
my-site/
| src/
| | index.html
| | etc...
| plugins/
open a terminal inside the my-site folder
# download the build script
wget https://raw.githubusercontent.com/easrng/ssg/refs/heads/main/build.ts -O build.ts
# make it executable
chmod +x build.tsto build your site, run ./build.ts in the my-site folder. by default the build script just copies every file from ./src to ./dist, but plugins in your ./plugins folder can rewrite files in ~any way.
plugins apply transformations to files with specific file extensions and are applied sequentially ordered according to their file names. (so 00_markdown.ts would run before 01_rewrite_links.ts, for example.)
for an example plugin, look at markdown.ts.